Ineos Styolution, a global styrenics supplier, has announced the preliminary results of two independent research projects conducting a life cycle assessment (LCA) analysis for depolymerised styrene according to ISO 14040 and ISO 14044 standards.
In the first, the production process for styrene from post-consumer polystyrene waste was compared to that of fossil-based styrene at laboratory scale. This project revealed greenhouse gas savings of 37%, with further CO2 reduction achievable through adaption of the energy mix. The LCA analysis was conducted within the framework of the ResolVe project, a research project funded by the German Federal Ministry for Education, in collaboration with InVerTec, a non-profit organization associated with the University of Bayreuth. InVerTec is specialised in providing pilot plants for conceptual and lab-scale research.
The second study was from IneosStyrolution, in collaboration with a commercial recycling partner and experts from the University of Manchester, and evaluated the greenhouse gas emissions of the process of polystyrene postconsumer waste collection, sorting, pre-treatment and extrusion, depolymerisation, distillation, at commercial scale. This was accomplished on the basis of the engineering design of an upscaled polystyrene depolymerisation plant and a three-step distillation process. The results show a 50% lower carbon footprint than that of traditional virgin (fossil-based) styrene monomer production.
“One driver for this high reduction of carbon dioxide is the fact that depolymerisation allows the recovery of styrene in a single process step avoiding several production steps needed to produce virgin styrene – resulting in a better performance in energy and resource efficiency compared to the production of virgin styrene. Another driver is the recycling of by-products and upscaling that enhances the resource efficiency compared with lab scale assessments,” explains Sven Riechers, vice president, Business Management, Standard Products, EMEA at Ineos Styrolution on the website providing more details about the company’s research.
“After having received the ICIS Award 2019 for polystyrene from recycled styrene via depolymerisation of recycled polystyrene, now we could for the first time prove that this technology is favourable regarding energy efficiency and CO2 footprint,” said Norbert Niessner, Global R&D/ Intellectual Property Director at INEOS Styrolution.
According to Ineos, there are some uncertainties due to the fact that a complete recycling plant is still at the design stage. Additional analysis will be done with a completed depolymerisation plant.
However: "I consider this first result to be very encouraging. At the same time, I am looking forward to results from a completed recycling plant,” said Riechers.